Total Suspended Solids. Total suspended solids (TSS) is that portion of the Total Solids that are retained on a no-ash glass fiber filter disc of approximately 0.45 mm pore size. The wetted and weighed filter disc is placed in a filtering apparatus and a suction is applied A measured volume of wastewater is passed through the filter. The filter containing the residue is then dried in an oven for one hour at 103 to 105°C. The sample is then cooled and weighed. The difference in weight of the dry filter before and after solids are passed through is the TSS milligrams (mg) of suspended solids per liter (l) of wastewater filtered Suspended Solids Filtering Apparatus
This inexpensive TSS test tells much about the wastewater character and can be run in less than two hours with fairly inexpensive equipment. The TSS test indicates whether it is likely that solids suspended in a wastewater can be removed by settling, floating or filtering. In order to remove all solids that were removed in the TSS Test, a filter similar to the TSS Filter paper (0.45 mm) must be used in full scale.
Total Dissolved Solids. The total dissolved solids (TDS) are the solids in the filtrate from the TSS test. The liquid which passes through the TSS filter is collected in a weighed dish and evaporated for an hour at 180°C ± 2°C. The dish is then re-weighed with the TDS equaling the difference between the dish weight before and after filling with filtrate and drying, in mg per liter of filtrate.Again, this inexpensive test can be run in less than two hours and will indicate the chemical or biological solids in a wastewater which cannot be removed through settling, floating or filtration.
Total Dissolved Solids (TDS) are the total amount of mobile charged ions, including minerals, salts or metals dissolved in a given volume of water, expressed in units of mg per unit volume of water (mg/L)
Total suspended solids (TSS) include all particles suspended in water which will not pass through a filter. Suspended solids are present in sanitary wastewater and many types of industrial wastewater.